CN108028452B

CN108028452B - Circulator module design with built-in directional coupler function and manufacturing method thereof

Info

Publication number: CN108028452B
Application number: CN201680046535.XA
Authority: CN
Inventors: 潘用周; 李东辉; 金美延
Original assignee: 3r Radio
Current assignee: 3r Radio
Priority date: 2015-09-24
Filing date: 2016-04-20
Publication date: 2021-01-12
Anticipated expiration: 2036-04-20
Also published as: KR101637923B1; CN108028452A; WO2017052019A1; US10530029B2; US20180159192A1

Abstract

The present invention relates to modularization of a Circulator (Circulator) and a Directional Coupler (Directional Coupler) for a wireless communication system, which can implement modularization by applying an electrical characteristic shared with the Circulator without implementing a line of the Directional Coupler (Directional Coupler) capable of sampling a high frequency signal, thereby improving the electrical characteristic of the wireless communication system and realizing miniaturization.

Description

Circulator module design with built-in directional coupler function and manufacturing method thereof

Technical Field

The invention relates to a circulator module design with a built-in directional coupler function and a manufacturing method thereof.

Background

A Non-reciprocal Circuit Element (Non-reciprocal Circuit Element) such as a Circulator (Circulator) or an Isolator (Isolator) is a high-frequency communication device that generally transmits a signal input through a predetermined port to a predetermined other port after rotating in one direction by Faraday Rotation (Faraday Rotation).

As shown in fig. 1, a circulator generally has three ports, and a signal input from each port is generally transferred to other adjacent ports having the same transmission coefficient and reflection coefficient. Each Port is in turn both an Input Port and an Output Port to an adjacent Port.

A circulator is generally located between a Power Amplifier (Power Amplifier) and an Antenna (Antenna) at a transmitting/receiving end of a wireless communication device, and transmits a signal amplified by the Power Amplifier to the Antenna side with a little loss. Instead, the signal may be blocked so that the signal reflected from the antenna or an unnecessary signal is not transmitted to the power amplifier side.

A Directional Coupler (Directional Coupler) is an artificial Reciprocal circuit (Passive Reciprocal Networks) having four ports, one of which can sample an input signal and the other of which has an electrical insulation property for the input signal. The four ports are all in a matching state, the directional coupler can operate completely, and a Transmission Line (Transmission Line) with 1/4 wavelengths (a quartz wavelength) is generally required. The directional coupler is used for sampling signals flowing towards a specific direction.

Fig. 2 is a schematic diagram showing a general directional coupler symbol.

As shown in fig. 2, in an ideal directional coupler, most of the signal input to the first port (P1) is transmitted to the second port (P2), and some very small signal is coupled at the third port (P3) but is not transmitted to the fourth port (P4). Conversely, the signal input to the second port (P2) is sampled at the fourth port (P4), but is not transferred to the third port (P3). That is, a directional coupler is an element designed such that a signal flowing in a particular direction can only be coupled at a particular port.

Fig. 3 is a schematic diagram showing the direction of the sampled signal transfer in the directional coupler with respect to the signal input direction.

As shown in fig. 3, a directional coupler is generally formed by connecting a termination resistor to one port. The signal inputted at the first port (P1) may be sampled at the third port (P3), whereas the coupled signal of the signal inputted to the second port (P2) is transferred to the port connected with the termination resistor and extinguished.

The amount of attenuation of the output signal (P2) of the input signal (P1) in the directional coupler is called Insertion Loss (Insertion Loss), the degree of Isolation in the fourth port (P4) of the input signal (P1) is called Isolation, the degree of Coupling in the third port (P3) of the input signal (P1) is called Coupling, and the value of the decoupling from the Isolation is called Directivity (Directivity). The directivity is a criterion for evaluating how well the input signal from the first port (P1) passes compared to the fourth port (P4), and is one of the most important evaluation items of the directional coupler.

The mathematical formula associated therewith is as follows.

[ mathematical formula ]

Insertion Loss(IL)＝10*log(P1/P2)

Isolation(I)＝10*log(P1/P4)

Coupling(C)＝10*log(P1/P3)

Directivity(D)＝10*log(P3/P4)

A directional coupler is typically located between the power amplifier and the circulator and the antenna as well as the circulator to sample the magnitude of the signal amplified from the power amplifier. As described above, only the input signal amplified from the power amplifier should be sampled at this time, and thus the Directivity (Directivity) of the coupler is an important electrical characteristic.

As the demand for wireless communication increases and communication technologies develop, not only the demand for corresponding communication devices increases, but also price competition increases, and thus, a demand for modularizing accessories that can reduce the electrical characteristics of the communication devices, particularly the Insertion Loss (Insertion Loss) of the system, is also generated.

Further research on the modularization of the directional coupler and the circulator is carried out. However, each component is electrically operated in a very different manner and is also structurally made of materials with completely different forms, so that the modularization thereof has many difficulties.

Fig. 4 is a circuit diagram of modularizing the directional coupler and the circulator. The modules of circulators and directional couplers realized with known techniques follow for the most part the structure of the module shown in fig. 4.

Some known techniques are to arrange the directional coupler within a laminated substrate on which the module is designed in such a way that a circulator is mounted. Such a module may cause the following problems. That is, heat generated at the circulator is transferred to the bottom surface of the module through the laminate substrate and thus cannot be efficiently transferred, and if it cannot be efficiently transferred, the temperature of the directional coupler in the circulator and the laminate substrate increases, eventually resulting in degradation of the electrical characteristics of the module. Further, the directional coupler and the circulator used for the base station and the repeater should endure a high output signal, but the laminated substrate with the built-in directional coupler transmits a high output high frequency signal through a plurality of via holes, and thus can endure a high output signal. As mentioned above, it is ultimately difficult to improve insertion loss in a modular manner to the extent that the individual elements are brought together. Moreover, some of the above-mentioned known technologies need to be manufactured by using expensive multilayer Teflon (Teflon) -based substrates or LTCC substrates, which results in increased manufacturing costs.

Disclosure of Invention

Technical subject

The invention aims to realize modularization of a Directional Coupler (Directional Coupler) and a Circulator (Circulator), and simplifies the module structure by utilizing mutually shared electrical characteristics, thereby improving the electrical characteristics and reducing the size of the module.

Technical scheme

An aspect of the invention may provide a circulator module including a circulator and a signal coupler. At this time, the signal coupler itself has no Directivity (Directivity), and the Directivity of the circulator module can be controlled by the Isolation characteristic of the circulator.

The signal coupler comprises a Coupling Line (Coupling Line) and a Main Transmission Line (Main Transmission Line), wherein the Coupling Line and the Main Transmission Line are mutually crossed at a certain interval to form a right angle.

The coupling line and the main transmission line are provided on mutually different layers of a printed circuit board.

The printed circuit board comprises a ground plane arranged between the main transmission line and the coupling line, the ground plane is provided with an opening part (open slot), and the degree of electric coupling (coupling) between the main transmission line and the coupling line is controlled by the opening part.

The main transmission Line and the Coupling Line are located on the same layer of the printed circuit board, and the remaining part of the Coupling Line is a Coupling Conductor (Coupling Conductor) having a jumper Line (Jump Line) shape on the main transmission Line in the crossing region, and the main transmission Line and the Coupling Line are electrically coupled (Coupling) by the Coupling Conductor.

Another aspect of the invention provides a circulator module including a circulator and a signal coupler. The signal coupler includes: a Main Transmission Line (Main Transmission Line) through which signals flow from the input port and the output port of the circulator; a Coupling Line (Coupling Line) that can sample a flowing signal through the main transmission Line; the signal flowing through the coupling line is provided through other ports distinguished from the input port and the output port; the signal coupler is itself non-directional; the directivity of the signal coupler is controlled by the Isolation characteristic of the circulator.

The coupling lines are insulated from the main transmission line at a certain interval and cross each other at right angles.

The printed circuit board comprises a ground plane arranged between the main transmission line and the coupling line, an opening (open slot) is arranged on the ground plane, and the degree of electric coupling (coupling) between the main transmission line and the coupling line is controlled by the opening.

The part of Coupling circuit and main transmission Line are located the same layer of printed circuit board, the remaining part of Coupling circuit is in the crossing region main transmission Line is last to be in the Coupling Conductor (Coupling Conductor) of jumper (Jump Line) form, through the Coupling Conductor take place electric Coupling (Coupling) between main transmission Line and the Coupling circuit.

Advantageous effects

The modularization of the circulator and the directional coupler has the advantages that a transmission line with 1/4 wavelength (lambda/4) length for forming the directional coupler can be eliminated, the insertion loss of the module can be greatly reduced, and the module specification is reduced. Moreover, the flow of high-output signals can be avoided through the via holes and the like, so that the product reliability is improved, and the operation of high-output high-frequency signals can be realized.

Drawings

FIG. 1 is a schematic diagram showing a common circulator symbol;

FIG. 2 is a schematic diagram showing a generic directional coupler symbol;

FIG. 3 is a schematic diagram showing the direction of sampled signal propagation with signal input direction in a directional coupler;

FIG. 4 is a circuit diagram of a circulator and directional coupler modeled in accordance with known techniques;

figure 5 is a schematic diagram illustrating a circulator module designed according to an embodiment of the invention;

figure 6 is a schematic diagram showing a circulator module designed according to another embodiment of the invention;

figure 7 is a circuit diagram of a circulator module according to an embodiment of the invention;

fig. 8 is a circuit diagram of a module in which the circulator signals are rotated in the opposite direction in the circulator module illustrated in fig. 7;

fig. 9 is a circuit diagram of a circulator module according to another embodiment of the invention.

Detailed Description

Embodiments of the present invention will be described below with reference to the accompanying drawings, but the described embodiments are some, not all, of the embodiments of the present invention and may be implemented in various forms. The terms used in the present specification are only for the understanding of the embodiments and do not limit the scope of the present invention. The singular forms of words used below also include the plural forms without the explicit opposite meaning.

Figure 5 is a stack diagram of a circulator module designed according to an embodiment of this invention.

As shown in fig. 5, the circulator module according to an embodiment of the invention may include a circulator 100 and four printed

circuit boards

110, 120, 130, and 140 stacked in sequence from top to bottom.

The

connection terminals

101, 102, 103 of the Center Conductor (Center Conductor) extending from the open surface of the circulator 100 made of soft magnetic material (soft magnetic material) are electrically connected to the input/output

connection Conductor terminals

111, 112, 113 provided on the uppermost layer 110 of the printed circuit board.

The uppermost layer 110 of the printed circuit board is provided with input/output

connection conductor terminals

111, 112, 113 for receiving the input/

output terminals

101, 102, 103 of the circulator 100, and the ground plane of the circulator is placed on the ground plane 116 of the uppermost layer 110 by means of the arrangement holes 217. The termination resistance 160 may be connected by an internal connection 205 from above to a conductor terminal portion 117 of the third layer 130.

An open face 121 is formed from the top to the second layer 120, and serves as an electrical coupling path between the main transmission line 115 provided in the uppermost layer 110 and the coupling conductor portion 131 of the coupling line 132 provided in the third layer 130. The coupling strength between the main transmission line 115 and the coupling line 132 can be adjusted by adjusting the size of the opening surface 121. The second layer 120 is provided with a conductor portion 123 removed from the third layer 130 to the uppermost layer 110 to allow a ground plane of a via to be connected.

In various embodiments of the present invention, the portion that includes main transmission line 115 and coupling line 132 may be referred to as a "signal coupler". The signal coupler is inherently non-directional. The signal coupler in the embodiment of fig. 5 may include an open face 121.

A coupling line 132 is provided from the upper to the third layer 130, and a coupling conductor portion 131 and a side connection terminal 133 are provided on the coupling line 132. A conductor portion 134 connectable to the via hole is provided on one side end of the coupling conductor portion 131.

The lowermost layer 140 provides input-

output terminals

141, 142, 143 and coupling terminals 144 of the module.

The circulator module illustrated in fig. 5 is operated electrically as follows.

The high frequency signal inputted through the first input/output terminal 141 provided at the lowermost layer 140 of the module is inputted to the connection terminal 114 of the uppermost layer 110 through the side connection 201, which is a portion connected along the side of the printed circuit board. A very small part of the input high-frequency signal is coupled to the coupling conductor portion 131 of the coupling line 132 intersecting the main transmission line 115, and the coupled high-frequency signal is connected to the coupling terminal 144 via the side connection 202 and is output. Most of the high-frequency signal is transmitted to the connection conductor portion 111 and further to the input-output connection terminal 101 of the circulator. The high frequency signal inputted to the circulator is transmitted to the output connection terminal 102 after being rotated clockwise by the faraday rotation phenomenon. The high-frequency signal is transmitted to the connection conductor portion 112, passes through the side connection 203, and is output through the second input/output terminal 142 provided in the lowermost layer 140.

On the other hand, since the high-frequency signal inputted through the second input/output terminal 142 is also rotated clockwise by the faraday rotation phenomenon of the circulator and then transmitted to the third input/output terminal 143, the high-frequency signal is not transmitted to the first input/output terminal 141 and the coupling terminal 144.

Figure 6 is a circulator module of another embodiment of the invention.

As shown in fig. 6, the

connection terminals

101, 102, 103 of the Center Conductor (Center Conductor) extending from the open surface of the circulator 100 are electrically connected to the input/output

connection Conductor portions

211, 212, 213 provided on the upper layer 210 of the printed circuit board.

The upper layer 210 of the printed circuit board is formed with

terminals

211, 212, 213 for receiving the input/

output terminals

101, 102, 103 of the circulator 100, and the ground plane of the circulator is arranged with the arrangement hole 217 provided in the upper layer ground plane 216. Further, a coupling line 221 is provided for electrically coupling with the main transmission line 215, and

terminals

222, 224 are provided for housing the coupling conductor 170 so that the main transmission line and the coupling line cross each other perpendicularly. A termination electrical group 160 is disposed between the conductor terminal portion 224 and the ground plane 216 for electrically matching the connection lines.

The lower layer 240 of the printed circuit board constitutes input-

output terminals

241, 242 and coupling terminals 244 of the module.

The circulator module illustrated on fig. 6 is powered on as follows.

The high-frequency signal inputted through the first input/output terminal 241 provided in the module lower layer 240 is inputted to the connection terminal 214 of the upper layer 210 through the side connection 251 of the substrate. A very small part of the input high-frequency signal is electrically coupled to the coupling conductor 170 of the coupling line 221 crossing from above the main transmission line 215, and the coupled high-frequency signal is connected to the coupling terminal 244 through the side connection 252 and output. In addition, most of the high-frequency signal is transmitted to the input connection terminal 101 of the circulator after being transmitted to the input/output connection conductor portion 211. The high frequency signal inputted to the circulator is rotated clockwise by the faraday rotation phenomenon and then transmitted to the output connection terminal 102. The high-frequency signal thus transmitted is connected to the output connection conductor 212 and is output through the second input/output terminal 242 provided in the lower substrate layer 240 via the side connection 253.

On the other hand, since the high-frequency signal inputted through the second input/output terminal 242 is transmitted to the third input/output terminal 243 while being rotated clockwise by the faraday rotation phenomenon of the circulator, the high-frequency signal is not transmitted to the first input/output terminal 241 and the coupling terminal 244.

Fig. 7 is a circuit diagram of a circulator module according to an embodiment of the invention.

As shown in fig. 7, the high-frequency signal input to the first port (P1) is transmitted to the circulator through a Main Transmission Line 1 (corresponding to the Main Transmission Line 115 shown in fig. 5 and 6). Here, a Coupling Line 2 (corresponding to the Coupling Line 132 shown in fig. 5 and 6) crossing the main transmission Line 1 at right angles thereto transfers a very small high-frequency signal sample to the third port (P3). Most of the high frequency signal transferred to the circulator 110 is rotated in a clockwise direction and transferred to the second port (P2). In contrast, the high frequency signal inputted to the second port (P2) is transmitted to the fourth port (P4) after the circulator 100 rotates. That is, the signal input to the second port (P2) is transmitted only to the fourth port (P4) and not to the third port (P3). Furthermore, the sampled signal extracted at the third port (P3) is only a high frequency signal input at the first port (P1), and thus has a higher Directivity (Directivity) than a high frequency signal coupled and transmitted from the second port (P2) to the third port (P3).

That is, the circulator 100 illustrated in fig. 7 blocks a signal transferred from the second port (P2) to the first port (P1), so that high directivity of a signal from the first port (P1) can be obtained at the third port (P3).

Fig. 8 is a circuit diagram of a module in which the signal rotation direction of the circulator in the circulator module illustrated in fig. 7 is reversed.

As shown in fig. 9, the high frequency signal input to the first port (P1) is coupled to the third port (P3), and the high frequency signal input to the second port (P2) is coupled to the fifth port (P5).

In an embodiment of the invention, the coupling line and the main transmission line are substantially crossed at right angles to each other at a certain interval. By substantially crossing at right angles is meant that the angle of crossing is slightly off from the exact right angle crossing configuration and 90. To avoid having directivity as well as the directional coupler of the known art, the maximum extended width of the crossover region of various embodiments of the present invention may be far less than 1/4 of the input signal frequency wavelength.

The circulator module described according to the embodiments of the present invention is also referred to as "directional module" or "directional circulator combination module".

The embodiments of the present invention are not limited to the above-described embodiments. That is, the printed circuit board used in the embodiment may be replaced by a three-dimensional plastic injection molding provided with a conductor portion, and the circulator mounted on the printed circuit board may be directly provided on the printed circuit board. The circulator module can also be implemented with a waveguide.

A person skilled in the art may use the above-described embodiments of the present invention to make various modifications and alterations to the present invention without departing from the scope of the invention. The claims are to be construed in a manner consistent with other claim elements not expressly recited therein.

Claims

1. A circulator module is characterized in that the circulator module comprises a circulator and a signal coupler, wherein the signal coupler comprises a Coupling Line (Coupling Line) and a Main Transmission Line (Main Transmission Line), the signal coupler does not have Directivity (Directivity) per se, and the Directivity of the circulator module can be controlled through the Isolation characteristic of the circulator;

the coupling line and the main transmission line are arranged on different layers of the printed circuit board;

2. The circulator module of claim 1 wherein the coupling lines are spaced apart from the main transmission line and intersect each other at right angles.

3. A circulator module as a circulator module including a circulator and a signal coupler, the signal coupler comprising: a Main Transmission Line (Main Transmission Line) through which signals flow from the input port and the output port of the circulator; a Coupling Line (Coupling Line) that can sample a flowing signal through the main transmission Line;

the signal flowing through the coupling line is provided through other ports distinguished from the input port and the output port; the signal coupler is itself non-directional; controlling a directivity of the signal coupler by an Isolation characteristic of the circulator;

the coupling lines and the main transmission line are insulated from each other at certain intervals and are crossed to form a right angle;

the Coupling Line is characterized in that a part of the Coupling Line and the main transmission Line are located on the same layer of a printed circuit board, the rest of the Coupling Line is a Coupling Conductor (Coupling Conductor) in a jumper Line (Jump Line) form on the main transmission Line in a crossing region, and electric Coupling (Coupling) occurs between the main transmission Line and the Coupling Line through the Coupling Conductor.